text: const color = (args) => {
    const color = (args[0] || '').trim();
    const text = (args[1] || '').trim();
    return '<span style="color:'+ color + ';">' + text + '</span>';
  };
  hexo.extend.tag.register('color', color, { ends: false });
  /* use: {% color [color] title %} */
  